[Vm-dev] VM Maker: BytecodeSets.spur-eem.16.mcz
commits at source.squeak.org
commits at source.squeak.org
Fri Oct 10 22:03:15 UTC 2014
Eliot Miranda uploaded a new version of BytecodeSets to project VM Maker:
http://source.squeak.org/VMMaker/BytecodeSets.spur-eem.16.mcz
==================== Summary ====================
Name: BytecodeSets.spur-eem.16
Author: eem
Time: 10 October 2014, 3:03:08.361 pm
UUID: d2a489bc-2ccd-44af-8c3a-2a739fcdeba9
Ancestors: BytecodeSets.spur-eem.15
Solve the extension problem for selector scanning.
Provide extensionsFor:in:into: to answer the extensions
preceeding the bytecode pc of an extended bytecode.
=============== Diff against BytecodeSets.spur-eem.15 ===============
Item was removed:
- ----- Method: EncoderForNewsqueakV4 class>>nonExtensionBytecodeAt:in: (in category 'instruction stream support') -----
- nonExtensionBytecodeAt: pc in: method
- "Answer the actual bytecode at pc in method, skipping past any preceeding extensions."
- | thePC bytecode |
- thePC := pc.
- [self isExtension: (bytecode := method at: thePC)] whileTrue:
- [thePC := thePC + (self bytecodeSize: bytecode)].
- ^bytecode!
Item was changed:
----- Method: EncoderForNewsqueakV4 class>>selectorToSendOrItselfFor:in:at: (in category 'instruction stream support') -----
selectorToSendOrItselfFor: anInstructionStream in: method at: pc
"If anInstructionStream is at a send bytecode then answer the send's selector,
otherwise answer anInstructionStream itself. The rationale for answering
anInstructionStream instead of, say, nil, is that potentially any existing object
can be used as a selector, but since anInstructionStream postdates the method,
it can't be one of them.
The compilcation is that for convenience we assume the pc could be
pointing to the raw send bytecode after its extensions, or at the extension
preceeding the raw send bytecode.
80-95 0101 i i i i Send Arithmetic Message #iiii
96-111 0110 i i i i Send Special Message #iiii
112-127 0111 i i i i Send Literal Selector #iiii With 0 Arguments
128-143 1000 i i i i Send Literal Selector #iiii With 1 Argument
144-159 1001 i i i i Send Literal Selector #iiii With 2 Arguments
160-175 1010 i i i i Send To Absent Implicit Receiver Literal Selector #iiii With 0 Arguments
224 11100000 aaaaaaaa Extend A (Ext A = Ext A prev * 256 + Ext A)
225 11100001 sbbbbbbb Extend B (Ext B = Ext B prev * 256 + Ext B)
238 11101110 i i i i i j j j Send Literal Selector #iiiii (+ Extend A * 32) with jjj (+ Extend B * 8) Arguments
239 11101111 i i i i i j j j Send To Superclass Literal Selector #iiiii (+ Extend A * 32) with jjj (+ Extend B * 8) Arguments
240 11110000 i i i i i j j j Send To Absent Implicit Receiver Literal Selector #iiiii (+ Extend A * 32) with jjj (+ Extend B * 8) Arguments
241 11110001 i i i i i j j j Send To Absent Dynamic Superclass Literal Selector #iiiii (+ Extend A * 32) with jjj (+ Extend B * 8) Arguments"
| byte |
byte := method at: pc.
byte < 80 ifTrue:
[^anInstructionStream].
byte <= 175 ifTrue:
["special byte or short send"
^byte >= 112
ifTrue: [method literalAt: (byte bitAnd: 15) + 1]
ifFalse: [Smalltalk specialSelectorAt: byte - 79]].
byte < 238 ifTrue:
[(byte >= 224 and: [byte <= 225]) ifTrue:
[^self extensionsAt: pc in: method into:
[:extA :extB :nExtBytes| | byteAfter index |
byteAfter := method at: pc + nExtBytes.
(byteAfter >= 238 and: [byteAfter <= 241])
ifTrue:
[index := ((method at: pc + nExtBytes + 1) bitShift: -3) + (extA bitShift: 5).
method literalAt: index + 1]
ifFalse: [anInstructionStream]]].
^anInstructionStream].
byte > 241 ifTrue:
[^anInstructionStream].
"they could be extended..."
+ ^self extensionsFor: pc in: method into:
- ^self extensionsAt: pc in: method into:
[:extA :extB :nExtBytes| | index |
index := ((method at: pc + 1) bitShift: -3) + (extA bitShift: 5).
method literalAt: index + 1]!
Item was removed:
- ----- Method: EncoderForSistaV1 class>>nonExtensionBytecodeAt:in: (in category 'instruction stream support') -----
- nonExtensionBytecodeAt: pc in: method
- "Answer the actual bytecode at pc in method, skipping past any preceeding extensions."
- | thePC bytecode |
- thePC := pc.
- [self isExtension: (bytecode := method at: thePC)] whileTrue:
- [thePC := thePC + (self bytecodeSize: bytecode)].
- ^bytecode!
Item was changed:
----- Method: EncoderForSistaV1 class>>selectorToSendOrItselfFor:in:at: (in category 'instruction stream support') -----
selectorToSendOrItselfFor: anInstructionStream in: method at: pc
"If anInstructionStream is at a send bytecode then answer the send's selector,
otherwise answer anInstructionStream itself. The rationale for answering
anInstructionStream instead of, say, nil, is that potentially any existing object
can be used as a selector, but since anInstructionStream postdates the method,
it can't be one of them.
The compilcation is that for convenience we assume the pc could be
pointing to the raw send bytecode after its extensions, or at the extension
preceeding the raw send bytecode.
96-111 0110 iiii Send Arithmetic Message #iiii #(#+ #- #< #> #'<=' #'>=' #= #'~=' #* #/ #'\\' #@ #bitShift: #'//' #bitAnd: #bitOr:)
112-119 01110 iii Send Special Message #iii #(#at: #at:put: #size #next #nextPut: #atEnd #'==' class)
120 01111000 UNASSIGNED (was: blockCopy:)
121 01111001 Send Special Message #value
122-123 0111101 i Send Special Message #i #(#value: #do:)
124-127 011111 ii Send Special Message #ii #(#new #new: #x #y))
128-143 1000 iiii Send Literal Selector #iiii With 0 Argument
144-159 1001 iiii Send Literal Selector #iiii With 1 Arguments
160-175 1010 iiii Send Literal Selector #iiii With 2 Arguments
* 224 11100000 aaaaaaaa Extend A (Ext A = Ext A prev * 256 + Ext A)
* 225 11100001 bbbbbbbb Extend B (Ext B = Ext B prev * 256 + Ext B)
** 234 11101010 iiiiijjj Send Literal Selector #iiiii (+ Extend A * 32) with jjj (+ Extend B * 8) Arguments
** 235 11101011 iiiiijjj Send To Superclass Literal Selector #iiiii (+ Extend A * 32) with jjj (+ Extend B * 8) Arguments"
| byte |
byte := method at: pc.
byte < 96 ifTrue:
[^anInstructionStream].
byte <= 175 ifTrue:
["special byte or short send"
^byte >= 128
ifTrue: [method literalAt: (byte bitAnd: 15) + 1]
ifFalse: [Smalltalk specialSelectorAt: byte - 79]].
byte < 234 ifTrue: "need to check for either extension cuz order of extensions is not restricted. so extB could preceed extA"
[(byte >= 224 and: [byte <= 225]) ifTrue:
[^self extensionsAt: pc in: method into:
[:extA :extB :nExtBytes| | byteAfter index |
byteAfter := method at: pc + nExtBytes.
(byteAfter >= 234 and: [byteAfter <= 235])
ifTrue:
[index := ((method at: pc + nExtBytes + 1) bitShift: -3) + (extA bitShift: 5).
method literalAt: index + 1]
ifFalse: [anInstructionStream]]].
^anInstructionStream].
byte > 235 ifTrue:
[^anInstructionStream].
+ "they could be extended..."
+ ^self extensionsFor: pc in: method into:
+ [:extA :extB :nExtBytes| | index |
+ index := ((method at: pc + 1) bitShift: -3) + (extA bitShift: 5).
+ method literalAt: index + 1]!
- ^method literalAt: ((method at: pc + 1) bitShift: -3) + 1!
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